The present invention relates to a sheet feeder for a writing system and similar writing machines and in particular to an automatic sheet feeder connected to a writing system including a platen, a printing station, a control unit for controlling the sheet feeder functions, a first container to contain fresh sheets, a second container to collect the printed sheets, guide means interposed between the first container and the second container, and moving means for driving the sheets along the guide means.
Many different sheet feeding devices for a writing system are well known. In a known type of feeder for writing machines, each single white sheet is sent from the container towards the driving roller through a selector activated by an electromagnet.
Therefore, the sheet passes around the platen and after printing, is driven towards the collecting container, until the driving-rollers pick it up and complete the transport in a direction opposite to the one of feeding.
Each written sheet is laid in the collecting container upon the preceding sheets already written so that at the end of printing the sheets are piled in such a way that the first sheet is under the following ones therefore, with the printed face oriented upwards, whereby the operator has to rearrange the sheets in the right order.
Furthermore, with such a device the driving-roller and the platen are moved by the same motor through a demultiplication gear and a driving-belt.
An electromagnetic clutch separates, selectively, the continuous feeding motor from the intermittent or interline feeding device.
Such a device presents some inconveniences. First of all, the separating device for the sheets to be sent to the platen is noisy and separates with difficulty the sheets stuck together due to electrostatic charges. As already mentioned, the written sheets are laid in the collector in an order contrary to that in which they were written. Furthermore, the feeding and the sheet recovery mechanism uses a completely mechanical transmission which, in addition to being noisy, has a tendency to breakdown.